[net-next PATCH v4 4/7] net: ravb: Refactor GbEth RX code path

From: Paul Barker
Date: Tue May 28 2024 - 11:07:30 EST


We can reduce code duplication in ravb_rx_gbeth().

Signed-off-by: Paul Barker <paul.barker.ct@xxxxxxxxxxxxxx>
---
Changes v3->v4:
* Used switch statements instead of if statements in ravb_rx_gbeth().

drivers/net/ethernet/renesas/ravb_main.c | 73 +++++++++++++-----------
1 file changed, 40 insertions(+), 33 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 7df7d2e93a3a..c9c5cc641589 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -817,47 +817,54 @@ static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
stats->rx_missed_errors++;
} else {
die_dt = desc->die_dt & 0xF0;
+ skb = ravb_get_skb_gbeth(ndev, entry, desc);
switch (die_dt) {
case DT_FSINGLE:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
+ case DT_FSTART:
+ /* Start of packet:
+ * Set initial data length.
+ */
skb_put(skb, desc_len);
+
+ /* Save this SKB if the packet spans multiple
+ * descriptors.
+ */
+ if (die_dt == DT_FSTART)
+ priv->rx_1st_skb = skb;
+ break;
+
+ case DT_FMID:
+ case DT_FEND:
+ /* Continuing a packet:
+ * Move data into the saved SKB.
+ */
+ skb_copy_to_linear_data_offset(priv->rx_1st_skb,
+ priv->rx_1st_skb->len,
+ skb->data,
+ desc_len);
+ skb_put(priv->rx_1st_skb, desc_len);
+ dev_kfree_skb(skb);
+
+ /* Set skb to point at the whole packet so that
+ * we only need one code path for finishing a
+ * packet.
+ */
+ skb = priv->rx_1st_skb;
+ }
+
+ switch (die_dt) {
+ case DT_FSINGLE:
+ case DT_FEND:
+ /* Finishing a packet:
+ * Determine protocol & checksum, hand off to
+ * NAPI and update our stats.
+ */
skb->protocol = eth_type_trans(skb, ndev);
if (ndev->features & NETIF_F_RXCSUM)
ravb_rx_csum_gbeth(skb);
+ stats->rx_bytes += skb->len;
napi_gro_receive(&priv->napi[q], skb);
rx_packets++;
- stats->rx_bytes += desc_len;
- break;
- case DT_FSTART:
- priv->rx_1st_skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_put(priv->rx_1st_skb, desc_len);
- break;
- case DT_FMID:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_copy_to_linear_data_offset(priv->rx_1st_skb,
- priv->rx_1st_skb->len,
- skb->data,
- desc_len);
- skb_put(priv->rx_1st_skb, desc_len);
- dev_kfree_skb(skb);
- break;
- case DT_FEND:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_copy_to_linear_data_offset(priv->rx_1st_skb,
- priv->rx_1st_skb->len,
- skb->data,
- desc_len);
- skb_put(priv->rx_1st_skb, desc_len);
- dev_kfree_skb(skb);
- priv->rx_1st_skb->protocol =
- eth_type_trans(priv->rx_1st_skb, ndev);
- if (ndev->features & NETIF_F_RXCSUM)
- ravb_rx_csum_gbeth(priv->rx_1st_skb);
- stats->rx_bytes += priv->rx_1st_skb->len;
- napi_gro_receive(&priv->napi[q],
- priv->rx_1st_skb);
- rx_packets++;
- break;
}
}
}
--
2.39.2